Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D207/00—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom
  • C07D207/02—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
  • C07D207/18—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member
  • C07D207/22—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
  • C07D207/24—Oxygen or sulfur atoms
  • C07D207/26—2-Pyrrolidones
  • C07D207/273—2-Pyrrolidones with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to other ring carbon atoms
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P25/00—Drugs for disorders of the nervous system
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D207/00—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom
  • C07D207/02—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
  • C07D207/30—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having two double bonds between ring members or between ring members and non-ring members
  • C07D207/34—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
  • C07D207/36—Oxygen or sulfur atoms
  • C07D207/38—2-Pyrrolones

Definitions

• the present invention is concerned with pharmacologically active pyrrolidine derivatives and with the method for their preparation. More particularly the object of the present invention is to produce compounds having the general formula ##STR2## wherein R represents hydrogen, acyl radical containing from 2 to 7 carbon atoms, saturated or unsaturated alkyl containing from 1 to 6 carbon atoms, aralkyl, cycloalkyl or aromatic radical R 1 and R 2 may be the same or different and represent hydrogen, saturated or unsaturated alkyl radical containing from 1 to 3 carbon atoms, cycloalkyl radical or R 1 and R 2 , together with the adjacent nitrogen atom, may form an heterocyclic ring optionally containing an additional heteroatom such as oxygen and nitrogen, and n represents an integer from 0 to 2 inclusive.
• acyl radical includes the acyl moiety of aromatic, aliphatic mono- or dicarboxylic acids such as acetic, propionic, butyric, n- valeric, hexanoic, malonic, succinic, benzoic acid and the like.
• alkyl, aralkyl, cycloalkyl and aromatic radical includes among others, methyl, ethyl, propyl, butyl, cyclopropylmethyl, pentyl, hexyl, allyl, propargyl, benzyl, vinyl, ethynyl, cyclopentyl, cyclohexyl, phenyl and the like.
• the substituents R 1 and R 2 may form together with the adjacent nitrogen atom, a piperidine, piperazine, oxazolidine or oxazoline nucleus.
• pyrrolidine compounds of formula I wherein R is an hydrogen atom, are prepared by subjecting compounds of formula II to decarboalkoxylation (a) to form 2,4-di-keto compounds of formula III, which in turn are subjected to hydrogenation (b) with formation of 4-hydroxy compounds IV and successive ammonolysis (c) to give final compounds Ia.
• R represents acyl, alkyl, aralkyl, cycloalkyl or aromatic radical
• compounds of formula Ia coming from step (c) are treated in a known manner with a suitable agent capable of modifying the hydroxy group in position 4 into the desired group.
• a suitable agent capable of modifying the hydroxy group in position 4 into the desired group.
• R° represents an acyl radical having from 2 to 7 carbon atoms, a saturated or unsaturated alkyl containing from 1 to 6 carbon atoms, aralkyl, cycloalkyl or aromatic radical while R 1 , R 2 and n have the above meaning.
• the sequence of the above reaction scheme may be reversed as to the ammonolysis step (c) and the introduction of the group R° at the hydroxy group in position 4 in step (d).
• the introduction of the R° group particularly in these derivatives in which R° represents an unsaturated alkyl containing from 1 to 6 carbon atoms, may be carried out directly on the ester compound IV and then the derivative so obtained submitted to ammonolysis to prepare compounds Ib.
• the decarboalkoxylation reaction (a) for the new compound of formula II which exists in its keto/enol form is effected by heating to reflux in a suitable solvent in the presence of water, which is necessary for the hydrolysis of the ester group of the starting product.
• the so obtained product, represented by formula III, is subjected to hydrogenation (a) with complex hydrides or, alternatively, with hydrogen in the presence of catalysts in suitable solvents.
• compound III is treated in an ether solvent or tetrahydrofuran with an approximately stoichiometric quantity of sodium borohydride.
• the ammonolysis reaction (c) of compound IV is effected according to known techniques, with ammonia or suitable amine of the formula HNR 1 R 2 in which R 1 and R 2 have the above meanings, with the exception that R 1 and R 2 are not both hydrogen.
• the compounds of the invention display a very interesting activity on the central nervous system: they were tested in comparison to controls and to the known product, which possesses the closest chemical structure and similar pharmacological behaviour, Piracetam, namely 2-(pyrrolidin-2-on-yl) acetamide.
• the compounds were tested in accordance with learning and memory screening carried out in the following manner:
• Climbing the pole during the first 15 seconds without stimulus is the anticipatory conditioned response CR 2
• climbing the pole during acoustic stimulus is the conditioned response CR 1 .
• the animals were treated by intraperitoneal or by oral route every day for 3 consecutive days one hour before each training session. Every day two training sessions were performed, namely at 9 a.m. and at 4 p.m. The learning rate of both CR 2 and CR 1 were considered.
• mice Male albino Swiss mice from our breeding were employed. The mice were 25 days old. The method and the apparatus were essentially those described by Essman W. B. on Psychopharmacologia (Berl) 9; 426, 1966. The passage from a light box into a dark one was punished by foot shock (1.3 m A - 5 sec.). Immediately after the trial a maximal electro convulsive shock (E.C.S.) 30 m A - 150 msec. 50 H z was given to the mouse by corneal electrodes. Compounds were administerd by intraperitoneal or by oral route 1 hour before the trial. The retest was performed 24 hours after E.C.S. Mice that did not cross from the light box into the dark one in 30 seconds were considered as non-affected by the retrograde amnesic effect of E.C.S.
• E.C.S. electro convulsive shock
• Control animals were submitted to E.C.S. or sham E.C.S.
• Ethyl N-(2-carbethoxyacetyl)-imino-diacetate in the form of an oil, is dissolved in anhydrous benzene and added at room temperature to a solution of 75.6 g sodium in 2700 ml of absolute ethyl alcohol.
• the solution is refluxed for 6 hours, cooled to room temperature, repeatedly extracted with water, the aqueous extracts collected together and acidified to pH 1 with hydrogen chloride, and a precipitate containing 2-(3-carbethoxy-4-hydroxy- ⁇ 3 -pyrrolidin-2-on-1-yl) ethyl acetate, which purified by recrystallization melts at 175°-179° C., is obtained.
• the solution is acidified with 20% hydrochloric acid, filtered in vacuo, evaporated in vacuo, taken up with methylene chloride and made anhydrous over magnesium sulphate; by filtration and evaporation, in vacuo and successive chromatography 2-(4-hydroxy-pyrrolidin-2-on-1-yl) ethyl acetate having a boiling point of 180° C. (with decomposition) is separated.
• the residue oil is slurried into isopropyl alcohol/ethyl ether and crystallized from isopropyl alcohol/isopropyl ether (20:80) to obtain 2-(4-acetoxypyrrolidin-2-on-1-yl) acetamide, which purified by chromatography melts at 84°-86° C.

Applications Claiming Priority (2)

Publications (1)

Family

ID=11219233

Family Applications (1)

Country Status (27)

Cited By (32)

Families Citing this family (6)

Citations (2)

Family Cites Families (3)

• 1975
  • 1975-08-13 IT IT26326/75A patent/IT1045043B/it active Protection Beyond IP Right Term
• 1976
  • 1976-08-09 CA CA258,677A patent/CA1077947A/en not_active Expired
  • 1976-08-09 IN IN1433/CAL/1976A patent/IN144871B/en unknown
  • 1976-08-09 AT AT589476A patent/AT353783B/de active
  • 1976-08-09 CS CS765174A patent/CS214766B2/cs unknown
  • 1976-08-09 NZ NZ181726A patent/NZ181726A/xx unknown
  • 1976-08-09 AR AR264270A patent/AR212176A1/es active
  • 1976-08-10 HU HU76IE754A patent/HU173742B/hu not_active IP Right Cessation
  • 1976-08-10 YU YU1964/76A patent/YU40147B/xx unknown
  • 1976-08-10 DE DE2635853A patent/DE2635853C2/de not_active Expired
  • 1976-08-10 SE SE7608938A patent/SE420599B/xx not_active IP Right Cessation
  • 1976-08-10 GB GB33243/76A patent/GB1550160A/en not_active Expired
  • 1976-08-11 CH CH1022576A patent/CH624935A5/de not_active IP Right Cessation
  • 1976-08-11 NL NLAANVRAGE7608946,A patent/NL179052C/nl not_active IP Right Cessation
  • 1976-08-11 DD DD19428776A patent/DD127966B3/de unknown
  • 1976-08-11 JP JP51095930A patent/JPS5822034B2/ja not_active Expired
  • 1976-08-11 NO NO762791A patent/NO146909C/no unknown
  • 1976-08-11 FR FR7624482A patent/FR2320741A1/fr active Granted
  • 1976-08-11 BE BE6045634A patent/BE845099A/xx not_active IP Right Cessation
  • 1976-08-12 DK DK365176A patent/DK156055C/da not_active IP Right Cessation
  • 1976-08-12 AU AU16797/76A patent/AU506651B2/en not_active Expired
  • 1976-08-12 ES ES450643A patent/ES450643A1/es not_active Expired
  • 1976-08-12 FI FI762314A patent/FI62290C/fi not_active IP Right Cessation
  • 1976-08-12 SU SU762388323A patent/SU663302A3/ru active
  • 1976-08-12 PL PL1976191773A patent/PL101471B1/pl unknown
  • 1976-08-12 US US05/713,901 patent/US4118396A/en not_active Expired - Lifetime
  • 1976-08-13 MX MX762906U patent/MX4717E/es unknown

Patent Citations (2)

Non-Patent Citations (2)

Also Published As

Similar Documents